path: root/comm/mailnews/db/mork/morkTableRowCursor.cpp

/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*-  */
/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

#ifndef _MDB_
#  include "mdb.h"
#endif

#ifndef _MORK_
#  include "mork.h"
#endif

#ifndef _MORKNODE_
#  include "morkNode.h"
#endif

#ifndef _MORKENV_
#  include "morkEnv.h"
#endif

#ifndef _MORKCURSOR_
#  include "morkCursor.h"
#endif

#ifndef _MORKTABLEROWCURSOR_
#  include "morkTableRowCursor.h"
#endif

#ifndef _MORKSTORE_
#  include "morkStore.h"
#endif

#ifndef _MORKTABLE_
#  include "morkTable.h"
#endif

#ifndef _MORKROW_
#  include "morkRow.h"
#endif

// 456789_123456789_123456789_123456789_123456789_123456789_123456789_123456789

// ````` ````` ````` ````` `````
// { ===== begin morkNode interface =====

/*public virtual*/ void morkTableRowCursor::CloseMorkNode(
    morkEnv* ev)  // CloseTableRowCursor() only if open
{
  if (this->IsOpenNode()) {
    this->MarkClosing();
    this->CloseTableRowCursor(ev);
    this->MarkShut();
  }
}

/*public virtual*/
morkTableRowCursor::~morkTableRowCursor()  // CloseTableRowCursor() executed
                                           // earlier
{
  CloseMorkNode(mMorkEnv);
  MORK_ASSERT(this->IsShutNode());
}

/*public non-poly*/
morkTableRowCursor::morkTableRowCursor(morkEnv* ev, const morkUsage& inUsage,
                                       nsIMdbHeap* ioHeap, morkTable* ioTable,
                                       mork_pos inRowPos)
    : morkCursor(ev, inUsage, ioHeap), mTableRowCursor_Table(0) {
  if (ev->Good()) {
    if (ioTable) {
      mCursor_Pos = inRowPos;
      mCursor_Seed = ioTable->TableSeed();
      morkTable::SlotWeakTable(ioTable, ev, &mTableRowCursor_Table);
      if (ev->Good()) mNode_Derived = morkDerived_kTableRowCursor;
    } else
      ev->NilPointerError();
  }
}

NS_IMPL_ISUPPORTS_INHERITED(morkTableRowCursor, morkCursor,
                            nsIMdbTableRowCursor)
/*public non-poly*/ void morkTableRowCursor::CloseTableRowCursor(morkEnv* ev) {
  if (this->IsNode()) {
    mCursor_Pos = -1;
    mCursor_Seed = 0;
    morkTable::SlotWeakTable((morkTable*)0, ev, &mTableRowCursor_Table);
    this->CloseCursor(ev);
    this->MarkShut();
  } else
    this->NonNodeError(ev);
}

// } ===== end morkNode methods =====
// ````` ````` ````` ````` `````
// { ----- begin attribute methods -----
/*virtual*/ nsresult morkTableRowCursor::GetCount(nsIMdbEnv* mev,
                                                  mdb_count* outCount) {
  nsresult outErr = NS_OK;
  mdb_count count = 0;
  morkEnv* ev = morkEnv::FromMdbEnv(mev);
  if (ev) {
    count = GetMemberCount(ev);
    outErr = ev->AsErr();
  }
  if (outCount) *outCount = count;
  return outErr;
}

/*virtual*/ nsresult morkTableRowCursor::GetSeed(nsIMdbEnv* mev,
                                                 mdb_seed* outSeed) {
  NS_ASSERTION(false, "not implemented");
  return NS_ERROR_NOT_IMPLEMENTED;
}

/*virtual*/ nsresult morkTableRowCursor::SetPos(nsIMdbEnv* mev, mdb_pos inPos) {
  mCursor_Pos = inPos;
  return NS_OK;
}

/*virtual*/ nsresult morkTableRowCursor::GetPos(nsIMdbEnv* mev,
                                                mdb_pos* outPos) {
  *outPos = mCursor_Pos;
  return NS_OK;
}

/*virtual*/ nsresult morkTableRowCursor::SetDoFailOnSeedOutOfSync(
    nsIMdbEnv* mev, mdb_bool inFail) {
  mCursor_DoFailOnSeedOutOfSync = inFail;
  return NS_OK;
}

/*virtual*/ nsresult morkTableRowCursor::GetDoFailOnSeedOutOfSync(
    nsIMdbEnv* mev, mdb_bool* outFail) {
  NS_ENSURE_ARG_POINTER(outFail);
  *outFail = mCursor_DoFailOnSeedOutOfSync;
  return NS_OK;
}
// } ----- end attribute methods -----

// { ===== begin nsIMdbTableRowCursor methods =====

// { ----- begin attribute methods -----

NS_IMETHODIMP
morkTableRowCursor::GetTable(nsIMdbEnv* mev, nsIMdbTable** acqTable) {
  nsresult outErr = NS_OK;
  nsIMdbTable* outTable = 0;
  morkEnv* ev = morkEnv::FromMdbEnv(mev);
  if (ev) {
    if (mTableRowCursor_Table)
      outTable = mTableRowCursor_Table->AcquireTableHandle(ev);

    outErr = ev->AsErr();
  }
  if (acqTable) *acqTable = outTable;
  return outErr;
}
// } ----- end attribute methods -----

// { ----- begin oid iteration methods -----
NS_IMETHODIMP
morkTableRowCursor::NextRowOid(  // get row id of next row in the table
    nsIMdbEnv* mev,              // context
    mdbOid* outOid,              // out row oid
    mdb_pos* outRowPos) {
  nsresult outErr = NS_OK;
  mork_pos pos = -1;
  morkEnv* ev = morkEnv::FromMdbEnv(mev);
  if (ev) {
    if (outOid) {
      pos = NextRowOid(ev, outOid);
    } else
      ev->NilPointerError();
    outErr = ev->AsErr();
  }
  if (outRowPos) *outRowPos = pos;
  return outErr;
}

NS_IMETHODIMP
morkTableRowCursor::PrevRowOid(  // get row id of previous row in the table
    nsIMdbEnv* mev,              // context
    mdbOid* outOid,              // out row oid
    mdb_pos* outRowPos) {
  nsresult outErr = NS_OK;
  mork_pos pos = -1;
  morkEnv* ev = morkEnv::FromMdbEnv(mev);
  if (ev) {
    if (outOid) {
      pos = PrevRowOid(ev, outOid);
    } else
      ev->NilPointerError();
    outErr = ev->AsErr();
  }
  if (outRowPos) *outRowPos = pos;
  return outErr;
}
// } ----- end oid iteration methods -----

// { ----- begin row iteration methods -----
NS_IMETHODIMP
morkTableRowCursor::NextRow(  // get row cells from table for cells already in
                              // row
    nsIMdbEnv* mev,           // context
    nsIMdbRow** acqRow,       // acquire next row in table
    mdb_pos* outRowPos) {
  nsresult outErr = NS_OK;
  nsIMdbRow* outRow = 0;
  morkEnv* ev = morkEnv::FromMdbEnv(mev);
  if (ev) {
    mdbOid oid;  // place to put oid we intend to ignore
    morkRow* row = NextRow(ev, &oid, outRowPos);
    if (row) {
      morkStore* store = row->GetRowSpaceStore(ev);
      if (store) outRow = row->AcquireRowHandle(ev, store);
    }
    outErr = ev->AsErr();
  }
  if (acqRow) *acqRow = outRow;
  return outErr;
}

NS_IMETHODIMP
morkTableRowCursor::PrevRow(  // get row cells from table for cells already in
                              // row
    nsIMdbEnv* mev,           // context
    nsIMdbRow** acqRow,       // acquire previous row in table
    mdb_pos* outRowPos) {
  nsresult outErr = NS_OK;
  nsIMdbRow* outRow = 0;
  morkEnv* ev = morkEnv::FromMdbEnv(mev);
  if (ev) {
    mdbOid oid;  // place to put oid we intend to ignore
    morkRow* row = PrevRow(ev, &oid, outRowPos);
    if (row) {
      morkStore* store = row->GetRowSpaceStore(ev);
      if (store) outRow = row->AcquireRowHandle(ev, store);
    }
    outErr = ev->AsErr();
  }
  if (acqRow) *acqRow = outRow;
  return outErr;
}

// } ----- end row iteration methods -----

// { ----- begin duplicate row removal methods -----
NS_IMETHODIMP
morkTableRowCursor::CanHaveDupRowMembers(
    nsIMdbEnv* mev,  // cursor might hold dups?
    mdb_bool* outCanHaveDups) {
  nsresult outErr = NS_OK;
  mdb_bool canHaveDups = mdbBool_kFalse;

  morkEnv* ev = morkEnv::FromMdbEnv(mev);
  if (ev) {
    canHaveDups = CanHaveDupRowMembers(ev);
    outErr = ev->AsErr();
  }
  if (outCanHaveDups) *outCanHaveDups = canHaveDups;
  return outErr;
}

NS_IMETHODIMP
morkTableRowCursor::MakeUniqueCursor(  // clone cursor, removing duplicate rows
    nsIMdbEnv* mev,                    // context
    nsIMdbTableRowCursor** acqCursor)  // acquire clone with no dups
// Note that MakeUniqueCursor() is never necessary for a cursor which was
// created by table method nsIMdbTable::GetTableRowCursor(), because a table
// never contains the same row as a member more than once.  However, a cursor
// created by table method nsIMdbTable::FindRowMatches() might contain the
// same row more than once, because the same row can generate a hit by more
// than one column with a matching string prefix.  Note this method can
// return the very same cursor instance with just an incremented refcount,
// when the original cursor could not contain any duplicate rows (calling
// CanHaveDupRowMembers() shows this case on a false return).  Otherwise
// this method returns a different cursor instance.  Callers should not use
// this MakeUniqueCursor() method lightly, because it tends to defeat the
// purpose of lazy programming techniques, since it can force creation of
// an explicit row collection in a new cursor's representation, in order to
// inspect the row membership and remove any duplicates; this can have big
// impact if a collection holds tens of thousands of rows or more, when
// the original cursor with dups simply referenced rows indirectly by row
// position ranges, without using an explicit row set representation.
// Callers are encouraged to use nsIMdbCursor::GetCount() to determine
// whether the row collection is very large (tens of thousands), and to
// delay calling MakeUniqueCursor() when possible, until a user interface
// element actually demands the creation of an explicit set representation.
{
  nsresult outErr = NS_OK;
  nsIMdbTableRowCursor* outCursor = 0;

  morkEnv* ev = morkEnv::FromMdbEnv(mev);
  if (ev) {
    AddRef();
    outCursor = this;

    outErr = ev->AsErr();
  }
  if (acqCursor) *acqCursor = outCursor;
  return outErr;
}
// } ----- end duplicate row removal methods -----

// } ===== end nsIMdbTableRowCursor methods =====

/*static*/ void morkTableRowCursor::NonTableRowCursorTypeError(morkEnv* ev) {
  ev->NewError("non morkTableRowCursor");
}

mdb_pos morkTableRowCursor::NextRowOid(morkEnv* ev, mdbOid* outOid) {
  mdb_pos outPos = -1;
  (void)this->NextRow(ev, outOid, &outPos);
  return outPos;
}

mdb_pos morkTableRowCursor::PrevRowOid(morkEnv* ev, mdbOid* outOid) {
  mdb_pos outPos = -1;
  (void)this->PrevRow(ev, outOid, &outPos);
  return outPos;
}

mork_bool morkTableRowCursor::CanHaveDupRowMembers(morkEnv* ev) {
  return morkBool_kFalse;  // false default is correct
}

mork_count morkTableRowCursor::GetMemberCount(morkEnv* ev) {
  morkTable* table = mTableRowCursor_Table;
  if (table)
    return table->mTable_RowArray.mArray_Fill;
  else
    return 0;
}

morkRow* morkTableRowCursor::PrevRow(morkEnv* ev, mdbOid* outOid,
                                     mdb_pos* outPos) {
  morkRow* outRow = 0;
  mork_pos pos = -1;

  morkTable* table = mTableRowCursor_Table;
  if (table) {
    if (table->IsOpenNode()) {
      morkArray* array = &table->mTable_RowArray;
      pos = mCursor_Pos - 1;

      if (pos >= 0 && pos < (mork_pos)(array->mArray_Fill)) {
        mCursor_Pos = pos;  // update for next time
        morkRow* row = (morkRow*)array->At(pos);
        if (row) {
          if (row->IsRow()) {
            outRow = row;
            *outOid = row->mRow_Oid;
          } else
            row->NonRowTypeError(ev);
        } else
          ev->NilPointerError();
      } else {
        outOid->mOid_Scope = 0;
        outOid->mOid_Id = morkId_kMinusOne;
      }
    } else
      table->NonOpenNodeError(ev);
  } else
    ev->NilPointerError();

  *outPos = pos;
  return outRow;
}

morkRow* morkTableRowCursor::NextRow(morkEnv* ev, mdbOid* outOid,
                                     mdb_pos* outPos) {
  morkRow* outRow = 0;
  mork_pos pos = -1;

  morkTable* table = mTableRowCursor_Table;
  if (table) {
    if (table->IsOpenNode()) {
      morkArray* array = &table->mTable_RowArray;
      pos = mCursor_Pos;
      if (pos < 0)
        pos = 0;
      else
        ++pos;

      if (pos < (mork_pos)(array->mArray_Fill)) {
        mCursor_Pos = pos;  // update for next time
        morkRow* row = (morkRow*)array->At(pos);
        if (row) {
          if (row->IsRow()) {
            outRow = row;
            *outOid = row->mRow_Oid;
          } else
            row->NonRowTypeError(ev);
        } else
          ev->NilPointerError();
      } else {
        outOid->mOid_Scope = 0;
        outOid->mOid_Id = morkId_kMinusOne;
      }
    } else
      table->NonOpenNodeError(ev);
  } else
    ev->NilPointerError();

  *outPos = pos;
  return outRow;
}

// 456789_123456789_123456789_123456789_123456789_123456789_123456789_123456789